Ford Motor Co. knowingly launched two low-priced, fuel-efficient cars with defective transmissions and continued selling the troubled Focus and Fiesta despite thousands of complaints and an avalanche of repairs, a Free Press investigation found.

The cars, many of which randomly lose power on freeways and have unexpectedly bolted into intersections, were put on sale in 2010-11 as the nation emerged from the Great Recession. At least 1.5 million remain on the road and continue to torment their owners — and Ford.

The automaker pushed past company lawyers’ early safety questions and a veteran development engineer’s warning that the cars weren’t roadworthy, internal emails and documents show. Ford then declined, after the depth of the problem was obvious, to make an expensive change in the transmission technology.

FREE PRESS INVESTIGATION: OUT OF GEAR

Instead, the company kept trying to find a fix for the faulty transmission for five years while complaints and costs piled up. In the interim, Ford officials prepared talking points for dealers to tell customers that the cars operated normally when, in fact, internal documents are peppered with safety concerns and descriptions of the defects.

The automaker faces thousands of angry customers, including former loyalists who say they will never buy another Ford; hundreds of millions in repair costs, many times without actually fixing the cars; and litigation so serious the company this spring warned investors of the financial threat posed by defects in what Ford called its DPS6 transmission.

Apart from the legal risks, “Total quality related spending for DPS6 could reach $3 billion,” read a 2016 internal report that projected the costs through 2020.

In a statement Wednesday to the Free Press, Ford said conversations about “challenges common to innovative new technology” were “normal exchanges.” It said many customers were unaccustomed to the feel of the transmission and acknowledged that, “After the new transmission was on the road, other problems developed. We acted quickly and determinedly to investigate the problems. … While we eventually resolved the quality issues, the solutions were more complex and took longer than we expected. We regret the inconvenience and frustration that caused some consumers.” It acknowledged discussion of switching to a different transmission and said it made choices based on what it thought “best for customers.”

To understand what happened, the Free Press reviewed hundreds of pages of internal documents, emails and court filings from the past decade in which Ford engineers and managers discussed concerns and sought to control damage from the dual-clutch transmission, which enabled the company to tout gas mileage near 40 mpg…